Powdering apparatus



May 24, 1932. s ps|u 1,859,304

POWDERING APPARATUS Filed Jul 20, 1929 :5 Sheets-Sheet 1 May 24, 1932. v s. LIPSIUS POWDERING APPARATUS Filed July 20, 1929 I5 Sheets-Sheet 2 May 24, 1932. s; ps us 1,859,304

POWDERING APPARATUS Filed July 20, 1929 3 Sheets-$heet 3 INVENTOR Patented May 24, 1932 UNITED STATES.

SAMUEL LTPSIUS, OF NEW YORK, N.

rownnnme Application filed July 270,

My invention relates particularly to apparatus for applying powder to sheets and specifically to the art of raised printing. The powder used in such processes is quite diflicult to handle and is quite expensive. It is therefore most desirable that the apparatus should be simple in construction and be able to apply the powder in the desired quantity to the proper parts of the sheeting to be treated and to remove the excess powder completely without wasting the powder or permitting it to escape into the room, where it may be troublesome to the operator of the machine. It is also mostdesirable that the same machine be able to apply powders of various characters and various degrees of fineness.

These objects I have attained by a special arrangement in which the sheets are carried through the machine automatically and the downward in the machine and then blown back into the distributing hopper. A single suction blower serves to collect excess powder and return it to a centrifugal separator and at the same time provide the necessary air pressure for blowing the excess powder from the sheets. Special provision is made for regulating the amount of the powder deposited on the sheets and other means is pro vided for inspecting the various parts of the apparatus while it is in action.

Fig. 1 is a side View and partial section of apparatus embodying my invention.

Fig. 2 is a similar view taken from the other side and having the hood thereon.

Fig. 3 is a front view of the apparatus, parts being shown in section.

Fig- 4 is a longitudinal sectional View of the powder hopper on a larger scale.

Fig. 5 is a detail plan in section of "the means for supportingthe relief bag.

nrrnnnrus 1929. Serial No. 379, 33.

The main part of the machine includes a housing 7 preferably supported onthe framework 8. The printed sheets are automatically carried through the housing by a conveyor 9 preferably formed of wire metal or the like. This conveyor is preferably driven by an electric motor 10 with chain .or belt connection such as 11, 12 and 13, the last being connected to a shaft or roller 14 which directly moves the conveyor. i

The powder hopper 15 has inclined sides and is closed at the top being provided with a door or cover 16, which is preferably hinged to facilitate inspection.

A plate 17 which extends across the hopper is arranged with its lower edge extending below the edge of thehopper to provide a narrow outlet 18 for the powder. This plate 17 is vibrated by a shaft 19 which is driven by a belt 20 at an appropriate speed. The

upper end of the plate 17 is suspended from a pair of hooks 21 which are adjustable back and forth by the rotation of the screw shafts 22.

Set screws 23 may be provided to lock each shaft 22 in its proper adjusted position. The front ends of the screw shafts 22 are both conveniently arranged so that the operator can adjust them as he looks into the front of the machine and sees the amount of powder which is falling upon the sheets. To facilitate the inspection the front edge of the housing is provided with a pivoted door 24. The plate 17 maybe provided with a weight 25 to assist in holding it in position.

Air is forced through the transverse pipe. 26 at ankinclination downward and toward the approaching powdered sheets so as to remove such powder as does not adhere to the, printed parts of the sheet or sheets. A suction blower 27 is driven by a motor 28 for removing the excess powderand re-conveying it to the distributing hopper 15. I i

A collecting receptacle 29 with inclined sides is arranged beneath the housing 7 to collect all the powder which does not remain on the printed sheets. The lower end of this receptacle 29 is connected by a removable pipe 30 to the intake of the suction blower. One side of the receptacle 29 is preferably provided with an opening which may have a cover 31 to facilitate access and which cover 7 may be transparent or have a transparent window to-facilitate inspection. A similar cover 31 is provided for the hopper 15. A screen 32 is preferably provided near the bottom of the receptacle 29' to prevent anything ezzcept powder from falling into the suction blower and interfering with the op eration of the same.

A centrifugal separator 33, or cyclone, as .it is sometimes called, is located above the powder hopper with its lower end discharging ing such powder as might be contained in the escaping air. A'skeleton ring or spider 39 serves as a convenient means for securing the bag to the pipe 37 and as a relief for excess pressure. The pressure through the outlet of the separator may be controlled by opening or closing the valve 40.

l/Vhen the parts of the apparatus are prop erly designed the construction above de scribed will operate automatically. In some cases, however, it may be desirableto properly adjust or balance the air pressure within the receptacle 29 and that within the hopper 1.5 by means of a connecting pipe 11. vWhen not needed this pipe can be omitted or closed entirely.

In operation the cardsor sheets to be powdered are deposited either automatically or by hand upon the conveyor 9, which takes them through the housing and discharges them at the other end preferably into the heater (not shown). The hopper 15 is partially filled with powder but the outlet 18 is too small for the powder to ordinarily escape. As the shaft 19 is rotated it vibrates the plate 17 sufliciently to allow the powder to sift through in a fine stream and fall upon the sheets. Of course it is only desired to have powder remain on the printed'portions of the sheets. v I therefore blow the excess powder from the sheets by the blower 27, the pressure being provided through the pipe 34, separator 33, outlet 35, connection 36 and outlet nozzle pipe 26.

It will be obvious from the inspection of the drawings and consideration of the foregoing description that the powder which is blown off will immediately tend to fall into the receptacle 29, which action is expedited by the suction of the blower 27 through the intake 30. For this purpose the top 4:2 of the hous ing is made quite low so that there will not be much space above the conveyor for the circulation of air and powder. Practically every particle of powder therefore is immediately sucked into the blower, being aided by gravity. The blower of course immediately forces the powder in the current of air upward through the pipe 34 and discharges it into the centrifugal separator 33 from :which it falls'into .the powder hopper 15.

There is of course some considerable air pressure in this hopper 15 which escapes partly through the outlet 35 at the top and partly through the passage 43 at one side of the hopper, as shown by the arrows. The air from the passage 43 blows upon the vibrating shaft 19 and-keeps it clean, separating the powder into very fineparticles. The air which escapes from the outlet pipe 35 goes to the nozzle 26 for removing the, excess powder 7 from the sheets as above described. Some of the air from the pipe 35 escapes 7 through the pipe 37 into the bag 38 carrying with it any particlesof powder that might accidentally not be removed by the separator, Which powder is deposited in the bag-38, the air escaping upwardly through the ring 39. By adjusting the valve 10 I am able to control the air pressure in the nozzle 26.

From the foregoing it will be seen that this apparatus has the special advantages of simplicity of construction and economy of operation. It will be seen thatI rely upon airpressure to remove the excess. powder from the sheets and that gravity and suction coact tocollect the removed powder and that air pressure returns the removed powder to the separator where gravity and centrifu-' gal force cause the powder to be redeposited in the supply hopper while the escaping air is returned to the housing for the purposeof removing the excess powder. It will thus be seen that the powder circulates through the machine and that no unused powder can escape from the apparatus.

The operator can readily adjust the amount of powder deposited on the sheets by simply turning the screw shaft 22 as he watches the operation of the machine.

A hood or housing may be mounted on the housing 7 to cover the upper parts of themaincluding a vibrating plate and a vibrator therefor and means for adjusting the position of said plate relative to said vibrator including a screw threaded member extending to the exterior and to the front of said hopper for ready manipulation by the operator.

2. A powdering machine comprising a housing, a hopper, a conveyor for stock, a powder receptacle, a device for feeding powder on said stock including a vibrating plate in said receptacle, a vibrator therefor, means for adjusting the position of said plate relative to said vibrator, including a screw threaded member extending to the exterior of and to the front of said hopper, and a hook carried by said member for supporting said plate.

8. A powdering machine comprising a housing, a conveyor for stock, a powder hopper having a restricted opening, means for feeding the powder onto the stock including a movable plate disposed in said restricted opening and a vibrator adapted to engage said plate, and means for adjusting said feeding means including a pair of screw threaded rods operatively connected to said plate and extending exteriorly of and to-the front of said hopper for ready manipulation.

4. A powdering machine comprising a housing, a conveyor movable in the housing, a hopper arranged above the conveyor for depositing powder upon sheets on the conveyo'r, a receptacle beneath the conveyor for collecting powder, an air nozzle arranged with an outlet above the conveyor for removing excess powder, a powder separator arranged above the hopper, a suction blower having its inlet connected to the receptacle beneath the conveyor and having its outlet connected to the separator and a pipe connecting the outlet of the separator with said nozzle.

5. A powdering machine comprising a housing, a wire meshwork conveyor movable in the housing, a powder hopper arranged above the conveyor for depositing powder upon sheets on the conveyor, a receptacle beneath the conveyor for collecting powder, an air nozzle arranged above the conveyor for removing excess powder, a centrifugal separator arranged above the hopper, a suction blower having its inlet connected to the receptacle beneath the conveyor and having its outlet connected to the separator and a pipe connecting the outlet of the separator with said nozzle and means for controlling the back pressure in the outlet from said separator.

6. A powdering machine comprising a housing, a conveyor movable in the housing, a powder hopper arranged above the conveyor for depositing powder upon sheets on the conveyor, a receptacle beneath the conveyor for collecting powder, an air nozzle arranged above the conveyor for removing excess powder, a powder separator arranged above the hopper, a suction blower having its inlet connected to the receptacle beneath the conveyor and having its outlet connected to the separator, a pipe connecting the outlet 1 SAMUEL LIPSIUS. 

